DANGEROUS CHEMICALS

The Guardian newspaper has been running a series about the "Chemical World" and I noticed a couple of items on Saturday

Isocyanates are linked to respiratory diseases such as asthma. So we're considering super glue. If an adult like me hasn't got asthma by now, then he never will; but maybe we should keep super glue well away from children (we probably do anyway, but only to avoid the temptation of junior applying glue to toilet seat .....) any maybe the family fridge isn't the best place to store the stuff.

Methylene chloride reacts with haemoglobin to form carboxyhaemoglobin, which stops blood cells carrying oxygen around the body. This is actually the same as carbon monoxide poisoning. And methylene chloride is the main constituent of Plastic Weld, which we all use on ABS plastic. Apparently the safe concentration is 25 parts per million. I doubt if methylene chloride is pernicious but I suggest we are all very careful with it: no smoking, no sniffing; work in a ventilated room, keep the cap on when not in use, keep away from children (who will be affected by far lower concentrations) and use an alternative solvent whenever possible. My personal preference is for methyl ethyl ketone.

Anyway happy modelling.

Reply to
John Bishop
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Not wishing to denegrade any of what you have said, I thinkit's probably fair to say that you are more likely to be killed or injured travelling by train, and that's one of the safest forms of transport.

I've heard of just one modeller (in the USA) passing away from his modelling activities. He was a professional painter and was using some paint on a daily basis. Not sure what chemical it incorporated, but it was regarded as fairly toxic and has subsequently been withdrawn from memory.

John.

Reply to
John Turner

John,

The problem I find with some statements about the use of chemicals in our hobby is that the people making the statements will not give a statement of the practical limits of use of chemicals. What exactly does 25 parts per million mean in real terms, and how long is one supposed to be exposed to any level greater than 25 parts per million to cause damage to themselves.

I remember getting into an argument with a contributor to another mailing list when talking about the problems associated with heating cyanoacrylate adhesives. I have used these adhesives to hold small pieces on a mandrel in a lathe for turning, then have broken the bond by heating the mandrel to get the piece off. The other contributor said that this was an unsafe method and should never be used. I asked how much cyanoacrylate adhesive had to be heated over what period to start causing problems. I never got an answer from him. But I did ask around other sources and found that the dangers of heating a small drop of cyanoacrylate sufficient to hold a small scale wheel on an 1/8" shaft would not generate enough fumes in the average workshop to cause a problem. I scratchbuild my wheels and the amount of this type of work would be measured as one wheel per month if I'm lucky :-)

I think most people in the hobby are aware of working in a well ventilated space when using any chemical. I have used Plastic Weld when building C&L track and I try to make sure that the room doesn't reek of the chemical and I keep my nose away from the bottle and the brush as far as is possible. I haven't suffered any ill effects over the last six years of building C&L track.

I believe that MEK is also a 'dangerous' chemical. I've used it with Plastikard for about 40 years and I'm still here and not suffering any ill effects, probably because my cumulative exposure to the chemical is quite low since I take heed of the need for ventilation, and my time using the chemical for my hobby is not really that great.

Most of these chemical warnings are to protect people in their place of work where the volumes of chemical used and the time people are exposed to them are very much greater than would normally be achieved by a hobbyist at home.

Jim.

Reply to
Jim Guthrie

Out of interest, do any of the glue or paint manufactures etc. supply 'Haz-chem' type data sheets for their hobby products, if they do then the risks will be real, if not then the risks will be minor when used as a hobby product I suspect.

Reply to
Jerry.

Of course, we should all beware of Dihydrogen Oxide, which we are exposed to frequently, and which can be lethal. Regards, Bill.

Reply to
William Pearce

Don't be such a wet blanket.

R.

Reply to
Richard

Or they're just covering their a***s.

MBQ

Reply to
MBQ

I believe that MEK in the eyes is not good, it oxidises the tissue and bliindness results. Most people of course are careful about sloshing the stuff around, but don't flick some off the brush. Mike in Bitish Columbia

Reply to
Michael Gray

"Michael Gray" wrote

Unleaded petrol isn't much fun either, I can assure you - ever had that spit back at you when filling your car (or motorcycle when it happened to me).

John.

Reply to
John Turner

Best antidote for that is to take it with twice its volume of peat flavoured ethyl alcohol.

Ken.

Reply to
Ken Parkes

If you want chemical safety information on MEK, etc., you can get it at

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Links are available for a wide range of chemicals, and also to web pages that explain some of the terminology.

Bevan

Reply to
Bevan Price

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